Comparison of estrogen and progesterone receptor status of circulating tumor cells and the primary tumor in metastatic breast cancer patients - Aktaş, Bahriye; Müller, Volkmar; Tewes, Mitra; Zeitz, Julia; Kasimir-Bauer, Sabine; Loehberg, Christian R.; Rack, Brigitte K.; Schneeweiss, Andreas; Fehm, Tanja (Gynecologic oncology, 2011)